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Home , Bone metastasis, Bone resorption

ANTICANCER RESEARCH 35: 6281-6286 (2015)

Prevalence of Deficiency in Patients with Metastases and

GERRIT STEFFEN MAIER1*, KONSTANTIN HORAS2*, ANDREAS ALOIS KURTH3, DJORDJE LAZOVIC1, JÖRN BENGT SEEGER4 and UWE MAUS1

1University Hospital of Orthopaedic Surgery, Pius-Hospital, Carl-von-Ossietzky-University, Oldenburg, Germany; 2ANZAC Research Institute, University of Sydney at Concord, Sydney, NSW, Australia; 3Department of Orthopaedic Surgery, Themistocles Gluck Hospital, Ratingen, Germany; 4Department of Orthopaedic Surgery, Justus-Liebig-University, Giessen, Germany

Abstract. Background/Aim: Breast and prostate are is the most common nutritional amongst the most prevalent malignancies globally and up to deficiency worldwide (1, 2). It is estimated to affect more 40% of patients will develop metastatic disease, particularly than 1 billion people of all races, age groups, and ethnic to the skeleton. Multiple myeloma is the most common backgrounds (3). As vitamin D is produced endogenously in cancer to affect bone with up to 90% of patients developing the skin via a UVB-dependent mechanism, the most bone lesions. Although several studies demonstrated that important risk factors for developing hypo-vitaminosis D endocrine changes such as vitamin D deficiency promote include low annual sunlight exposure, darker skin tone and secondary cancer growth in bone, relatively few have heavy sunscreen use (4, 5). reported its prevalence. For this reason, the purpose of the Traditionally, the bioactive 1,25-dihydroxyvitamin D present study was to evaluate the prevalence of [1,25(OH)2D] acts via the vitamin D receptor (VDR) and has hypovitaminosis D in patients with bone metastases and hormonal actions mainly in the kidney, bowel, parathyroid multiple myeloma. Patients and Methods: Serum 25-OH-D and bone affecting and . Low levels of patients with metastatic were vitamin D levels have been associated with an increased risk measured on admission. Statistical analyses was performed of cardiovascular diseases, type 2 diabetes as well as mental to evaluate for possible confounders of hypo-vitaminosis D. illness (6-8). Moreover, several studies suggest that vitamin Results: We found a widespread and alarming rate of vitamin D also regulates innate and adaptive immune function, by D deficiency in patients with metastatic bone disease and activating macrophages, dendritic cells and lymphocytes (9, multiple myeloma. Of note, patients with bone metastases 10). In addition, vitamin D deficiency leads to an increase in due to , and multiple myeloma bone turnover and secondary hyper-parathyroidism rarely reached sufficient serum 25-OH-D levels. Conclusion: promoting cortical bone loss. In certain cases, severe vitamin It is of utmost clinical importance to assess vitamin D levels D deficiency can also result in (11). in cancer patients, especially in those with, or at high risk Furthermore, vitamin D deficiency has been linked to the of developing metastatic bone disease. pathogenesis of and hip fractures (12, 13). Apart from its effects on bone, several studies reported an association between low vitamin D levels and increased cancer risk (e.g. in breast, prostate and colon ) (14, 15). Epidemiological data suggest that vitamin D deficiency is associated with increased prostate cancer incidence and *These Authors contributed equally to this study. related deaths (16, 17). Patients with multiple myeloma showed a high prevalence of vitamin D deficiency in two Correspondence to: Dr Gerrit S. Maier, Klinik für Orthopädie und recent studies (18, 19). Association of vitamin D deficiency spezielle Orthopädie, Universitätsklinik für Orthopädie und with higher serum CRP, serum creatinine and International Unfallchirurgie, Pius Hospital, Medizinischer Campus Universität Staging System stage at the time of diagnosis suggested that Oldenburg, Georgstrasse 12, 26121 Oldenburg. Tel: +49 4412291588, vitamin D deficiency may portend poorer outcomes in Fax: +49 4412291569, e-mail: [email protected] patients with multiple myeloma (19). In breast cancer it was Key Words: Vitamin D deficiency, vitamin D, bone metastases, bone shown that vitamin D exerts anti-proliferative and pro- tumor, bone cancer. apoptotic effects on breast cancer cells (20, 21). Moreover,

0250-7005/2015 $2.00+.40 6281 ANTICANCER RESEARCH 35: 6281-6286 (2015)

Table I. Patients' characteristics prevalence and progression, relatively few have reported its prevalence. The purpose of the present study was to evaluate Characteristics Breast Prostate Multiple the prevalence of hypovitaminosis D in patients with bone cancer cancer myeloma metastases derived from different primary tumors and No. of patients 89 58 49 multiple myeloma. Moreover, the aim was to elucidate Men sex 0 58(100%) 29 (59%) whether or not there are significant differences in 25- Female sex 89 (100%) 0 20 (41%) hydroxyvitamin D (25-OH-D) serum levels between the Mean age in years 51 (+/-9.3) 59 (+/-8.2) 57.4 (+/-1.6) patient groups tested. Alcoholism 2 (3%) 3 (5%) 1 (2%) Nicotine Abuse 46 (51%) 27 (46%) 20 (40%) Obesity (BMI >30kg/m2) 17 (19%) 13 (22%) 11 (22%) Patients and Methods Osteoporosis 9 (10%) 4 (8%) 6 (12%) Hypertension 47 (53%) 25 (43%) 23 (47%) Between January 1st, 2011 and December 31st, 2012, serum 25- Cardiovascular disease 18 (20%) 14 (24%) 13 (27%) OH-D levels (referred to as vitamin D) of 196 patients consecutively (chronic/congestive admitted to the orthopaedic department of the university hospital in heart failure, Mainz, Germany (50˚ N latitude), were measured on admission. myocardial infarction) Patients were admitted due to bone metastases of breast cancer Thyreotic Abnormality 31 (35%) 23 (40%) 18 (37%) (n=89), prostate cancer (n=58) or multiple myeloma (n=49). (Hypo-/Hyperthyroidism) Generally, was taken on the day of admission. The mean age Pulmonary disease 9 (10%) 7 (12%) 8 (16%) of the patients was 58 years (+/-8.1 years) (Table I). (COPD, Asthma) Measurement of serum 25-OH-D was standardised; the hospital Renal failure 11 (12%) 7 (12%) 8 (16%) ® Infectious diseases 2 (2%) 1 (2%) 0 laboratory used the ARCHITECT 25-OH Vitamin D assay (Abbott (HIV, Hepatitis A, B, C, GmbH & Co KG, Wiesbaden-Delkenheim, Germany). Informed Tubercolosis) consent was obtained from all individual participants included in the Oral Vitamin D 16 (18%) 6 (10%) 9 (18%) study. All procedures performed in studies involving human participants supplementation were in accordance with the ethical standards of the institutional and Diabetes 19 (21%) 13 (22%) 11 (22%) national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. As yet there is no universally accepted classification of vitamin D levels, we defined sufficient vitamin D status as a serum 25-OH- D level of above 30 ng/ml. Vitamin D inadequacy was defined as serum 25-OH-D level under 30 ng/ml and further divided into vitamin D deficiency has been shown to increase the vitamin D insufficiency (20 to 30 ng/ml) and vitamin D deficiency incidence of breast cancer and to accelerate disease (under 20 ng/ml), as described previously (3). Hypovitaminosis D progression (22, 23). was defined as a serum 25-OH-D level below 20 ng/ml according to Multiple myeloma is the most common cancer to affect bone the definition of the World Health Organization. with up to 90% of patients developing bone lesions (24). It is Patients’ demographic variables and background data were characterised by increased bone resorption and the majority of evaluated by retrospective chart review and were used as potential confounders. Included variables were age, sex, origin of the primary patients have pathological fractures at diagnosis (25). tumor, body-mass index (BMI), comorbidities, oral medication and Secondary spread of prostate cancer and breast cancer any vitamin D supplements taken before admission. Patients’ frequently involves metastases to bone, resulting in debilitating characteristics were summarised using either means and standard , immobility, fractures and spinal compression syndromes deviations or frequencies and percentages. (4, 26). Recently, it was demonstrated in a murine model, that All patients with a valid 25-OH-D measurement were included vitamin D deficiency promotes breast cancer growth in bone, in the statistical analysis. partly through direct anti-proliferative effects of vitamin D on Serum Vitamin D levels were compared between different sexes, as well as between different primary tumors using the Student’s t- cancer cells, but also indirectly via modulation of the bone test for independent samples. microenvironment (20, 27). These findings are consistent with After the initial analyses, an analysis of covariance (ANCOVA) clinical observations showing that accelerated bone turnover is and analyses of variance (ANOVA) were performed to evaluate associated with higher rates of skeletal-related events and possible effects of known risk factors of vitamin D deficiency within poorer prognosis in patients with breast cancer (28). the tested groups. ANCOVA was used to control for the effect of Additionally, there is in vitro evidence that vitamin D age and ANOVA’s were used to analyse possible effects of age, renal 2 deficiency itself has an impact on the invasive potential of failure, obesity (defined as a BMI over 30 kg/m ), diabetes mellitus, nicotine abuse, osteoporosis, hypertension, cardiovascular diseases, human breast cancer cells (29). In another study, it was shown alcoholism, hyperthyroidism/hypothyreosis, pulmonary diseases, that vitamin D deficiency accelerated prostate cancer growth infectious disease and to check for possible interactions between the in bone through modulating the bone environment (30). group variable and the above-mentioned categorical variables. Although numerous studies have demonstrated a Statistical analyses was performed using IBM SPSS Statistics correlation between vitamin D deficiency and cancer risk, software (Ver. 21; IBM Corporate, Armonk, NY, USA ).

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Results cells parasitise the bone marrow and control the local environment to favour their own prosperity (33, 34). However, A total of 196 patients participated in this study. 59.4 % of it is still largely unknown whether tumor cells specifically study participants were women, 40.5% men. Ages ranged target a ‘metastatic niche’ in bone and what facilitates tumor from 41 to 97 years, with a mean age of 58 (±8.1) years. cells to settle within the bone microenvironment. Serum 25-OH-D levels for all participants were normally It has been previously shown in mouse models that distributed, with a mean of 15.2 ng/ml (±7.2 ng/ml). Lowest increased bone turnover accelerates the intra-skeletal growth measured level was <8 ng/ml, highest measured level was of breast cancer cells. Furthermore, it was demonstrated that 48.5 ng/ml. vitamin D deficiency promotes breast cancer growth in bone Patients with bone metastases of breast cancer showed a partly through changes in the bone microenvironment, but mean serum 25-OH-D level of 15.3 ng/ml (±4.7 ng/ml). also through direct effects of vitamin D on cancer cells (20, Patients with metastatic bone disease due to prostate cancer had 27). These experimental findings provide a conclusive an average serum vitamin D level of 14.7 ng/ml (±8.3 ng/ml). rationale for the clinical observation that accelerated bone In the patients group of bone lesions due to multiple myeloma, turnover is associated with higher rates of skeletal related the mean 25-OH-D level was 14.8 ng/ml (±6.3 ng/ml). events and poorer prognosis of patients with breast cancer The Student’s t-test showed no significant difference (28). Often, vitamin D deficiency results in an increased between serum 25-OH-D levels of the 3 patient groups. No level of (PTH) stimulating calcium statistical difference in vitamin D levels was found in respect mobilisation from skeletal stores (3, 35). PTH increases the to male patients with bone metastases (mean vitamin D level expression of RANKL (receptor activator of NF-κB Ligand) of 14.94 ng/ml) compared to female patients with bone stimulating and recruiting elevating bone metastases (15.04 ng/ml) (p=0.78). resorption. Cancer cells are able to secrete PTH-related Following the univariate analyses, analyses of protein (PTHrP) that closely mimics PTH actions promoting covariance were performed to evaluate the effect of age on in bone (31, 33). These modulations in the bone vitamin D levels in the tested groups. Analyses of variance microenvironment stimulate the release of other growth were performed to check for main effects and interactions factors from the bone matrix, such as insulin-like growth for nicotine abuse, gender, renal failure, obesity and factors, TGF-ß and other cytokines resulting in the diabetes mellitus on vitamin D levels in the subgroups. previously described ‘vicious cycle’ of tumour growth in After adjustment for the covariate age, mean differences bone (26, 33, 36). Endocrine changes such as vitamin D between our patient groups were similar (Grade of deficiency contribute to a release of these growth factors Freedom F=0.03; p=0.71). After adjustment for possible providing a ‘fertile’ soil for tumour cells to thrive (37). confounders, we found no significant main effect of the Notably, it is known that release of bone-derived growth tested variables obesity (p=0.98), nicotine abuse (p=0.31) factors and cytokines from resorbing bone can both attract and diabetes mellitus (p=0.077) on serum vitamin D levels cancer cells and facilitate their growth and proliferation (32). in the tested groups. Vitamin D levels were not dependent Moreover, the bone microenvironment houses on gender (p=0.57), renal failure (p=0.69) and other tested haematopoietic stem cells (HSC) that persist in, as possible confounders. commonly referred to, the stem niche. It has recently been suggested, that metastatic tumor cells target this HSC Discussion niche and compete with HSCs for the occupancy of that niche within the bone microenvironment (38). Manipulating Breast and prostate cancer as well as multiple myeloma have the size of the niche has been shown to alter the frequency of a high propensity to metastasise to the skeleton and once bone metastases. Most notably, in a study using metastatic tumors have spread to bone, they are usually incurable. prostate cancer, it has been demonstrated that an expansion Moreover, bone metastases have devastating consequences of this HSC niche with PTH treatments resulted in resulting in pathological fractures, severe pain, life- significantly a greater number of bone metastases (34). Thus, threatening hypercalcemia and nerve compression syndromes changes of the bone microenvironment due to low vitamin D (31). Besides a significant decline in quality of life, levels might also result in a conditioning of the pre- metastatic bone disease may eventually lead to death due metastatic niche for cancer cells increasing skeletal entirely to skeletal complications (32). For this reason, it is susceptibility to cancer (33, 37, 39). of utmost importance to identify factors that initiate and Collectively, it has been demonstrated that vitamin D promote the growth of bone metastases. deficiency promotes the growth of bone metastases. In In recent years, it has become evident that the bone addition, there is evidence that vitamin D deficiency microenvironment plays a pivotal role in the engraftment and increases skeletal susceptibility to cancer metastases. Further, growth of metastatic cancer cells. Upon arrival in bone, cancer metastatic destruction of bone reduces its load-bearing

6283 ANTICANCER RESEARCH 35: 6281-6286 (2015) capacity and the probability of developing a pathological 5 Holick MF: Environmental factors that influence the cutaneous fracture increases with the duration of metastatic production of vitamin D. Am J Clin Nutr 61:638S-645S, 1995. involvement (32). The development of a pathological fracture 6 Mattila C, Knekt P, Mannisto S, Rissanen H, Laaksonen MA, is devastating to cancer patients. Thus, adequate clinical Montonen J and Reunanen A: Serum 25-hydroxyvitamin D concentration and subsequent risk of type 2 diabetes. Diabetes management of patients with, or in high risk of secondary Care 30: 2569-2570, 2007. cancer spread to bone is pivotal. This suggests that the 7 Giovannucci E, Liu Y, Hollis BW and Rimm EB: 25- maintenance of adequate vitamin D levels is of utmost hydroxyvitamin D and risk of myocardial infarction in men: a clinical importance. Hence, correcting vitamin D deficiency prospective study. 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